Railway car conditioning



y 1934- s. M. ANDERSON 1,957,431

I RAILWAY CAR CONDITIONING Filed Feb. 16, 1932 6 Sheets-Sheet 1 INVENTOR \fah wz/ A4 finder-ac r7 BY 9w I p W 7' -5' ATTORNEY y 1934- s. M. ANDERSON 7,

RAILWAY CAR CONDITIONING Filed Feb. 16, 1932 6 Sheets-Sheet 3 INVENTOR iznfll Qndwuow H ATTORNEY May 8, 1934.

v s. M. ANDERSON 1,957,431

RAILWAY CAR CONDITIONING Filed Feb, 16, 1932 6 Sheets-Sheet 4 4/7727? STOP/76E wan/v6 TaWE/P 57 I INVENTOR l Coal/N6 Sana/a! 4- F R c1 L Tami? J Mal/v5 3; 49 BY a4 QM PW 46 45 14 ATTORNEY May 8, 1934. s. M; ANDERSON RAILWAY CAR CONDITIONING Fild Fbfle, 1952 e Sheet's Sheet e INVENTOR sdllvul M. findezuofl BY JMWK H: ATTORNEY I Patented May 8, 1934 UNITED- STATES PATENT OFFICE RAILWAY CAR CONDITIONING Application February 16, 1932, Serial No. 593,241

4' Claims.

This invention relates to the conditioning of air for vehicles and relates more particularly to the conditioning of air circulated through railway cars.

It is now becoming well known that human comfort requires that the air within an enclosure should be not only circulated to provide sufiicient ventilation, but should in winter be warmed with moisture added to maintain the proper relative humidity and in summer should be cooled and moisture extracted from it to overcome the exces- Among the difiiculties which present themselvesare the lack of space in a railway car which already of necessity has had to accommodate the maximum of equipment in the minimum of space,

the excessive refrigeration equipment which would have to be carried if the ordinary method of conditioning buildings were followed, the changing temperature conditions through which a railway cars must pass, the cost of the equipment, and other difiiculties.

An object of this invention is to economically condition the air for railway cars and other vehicles.

Another object of the invention is to provide air conditioning equipment for vehicles which utilizesa minimum of space.

Another object of the invention is to provide air conditioning equipment for vehicle, in units which are compact, airtight, and can be easily assembled.

Another object of the invention is to provide a railway car with an air conditioning system, the various units of which are placed at locations most advantageous for their operation.

Another object of the invention is to cool the motive equipment of a refrigeration system.

Another object of the invention is to provide a refrigeration unit comprising a cooling tower, compressor and compressor driving unit.

In one embodiment of the invention a refrigerant compressor, driven by an internal combustion engine, compresses the refrigerant which is allowed to cool in a condenser and then to expand in expansion coils immersed in water contained within a cooler tank. The water in the cooler tank is cooled by expansion of the refrigerant and the cooled water is circulated through a cooling chamber where it may be made to cool the air by means of a spray or by means of a surface cooler through which the water is circulated. The water leaving the cooling chamber passes back to the cooler tank where it is again cooled in the next cycle. Water in the condenser is heated in cooling the hot refrigerant before its expansion and is circulated to a cooling tower and expelled in the form of a spray in the cooling tower; and air from the outside is passed through the spray, and by evaporation cools the condenser water to approximately the wet bulb temperature of the cooling air. The condenser water is recirculated again through the condenser and the refrigerant is again recirculated through the compressor. The invention comprehends apparatus constructed most compactly and disposed most advantageously to take advantage of the conditions which have been found to be present in vehicles such as railway cars, for example.

In another embodiment of the invention, the refrigerant compressor is operated by an electric motor which may be driven from a generator connected to an axle of a railway car. The cooler and condenser of the embodiment described above are both omitted. The refrigerant is piped directly to the cooling chamber and expands there in surface cooler piping and extracts the heat from the air passing through the cooling chamber, directly. No condenser is used, the condenser coils being placed directly in the cooling tower where the return water from a spray which is cooled by evaporation is in contact with the coils of the pipe, thus cooling the heated refrigerant in this pipe, directly.

Other objects and features of the invention will be apparent from the following description of the embodiments of the invention illustrated by the drawings, of which:

Fig. 1 is a partial view of a portion removed of a railway car, showing the general arrangement of an installation of air conditioning equipment according to this invention;

Fig. 2 is a side view of the ventilating fan and cooling chamber through which the air to be circulated through the railway car is passed;

Fig. 3is an end view partially in section of one form of a cooling chamber which can be used with Figs. 1 and 2, utilizing sprays for cooling the air; i A

v Fig. 3a is a top view in section of the cooling chamber of Fig. 3; i I

Fig. 4 is an end view, partially in section, of another form of cooling chamber which may be used with the systems of Figs. 1 and2, utilizing cooling coils for cooling the air;

Fig. 5 is a view looking downward on the unit shown by Figs. 1 and 2 and shows the arrangement of the ventilating and cooling apparatus installed in a railway car;

Fig. 6 is a sectional view along the line 606 of Fig. 5;

Fig. '7 is a sectional end elevation taken along the line 7-7 of Fig. 5;

Fig. 8 is a plan view looking downward with the car floor removed of one embodiment of the condenser and refrigeration equipment utilizing an internal combustion engine as the motive power;

Fig. 9 is a side elevation with the side sheet removed of the cooling tower and refrigeration equipment shown by Fig. 8;

Fig. 10 is a piping diagram showing the refrigerant piping, the cooling water piping, and the chilled water piping, and is a diagrammatic view looking from the side of the car;

Fig. 11 is an aerograph illustrating diagrammatically the passage of the air through a cooling chamber and railway car with the temperatures at various points of the circuit;

Fig. 12 is an aerograph for the condenser cooling tower circuit;

Fig. 13 is a diagrammatic view of one embodimentof a complete air conditioning system, according to this invention, illustrating the conditioning of air, the circulation of air, and the circulation of the refrigerant, the cooling water, and the chilled water;

Fig. 14 is a side elevation with the side sheet removed of another embodiment of a cooling tower and refrigeration equipment, utilizing an electric motor as a motive power, and having the condenser coils placed in contact with the spray water in the cooling tower;

Fig. 15 is a plan view lookingdownward with the car floor removed of the apparatus shown by Fig. 14, and

Fig. 16 is a diagrammatic view of another embodiment of a complete air conditioning system illustrating the conditioning of air, circulation of air, circulation of the refrigerant, and cooling water. No condenser is used, the condenser coils being placed directly in the cooling tower, and there is no chilled water circuit, the refrigerant being expanded directly in a surface cooler in the cooling chamber.

This invention comprises a complete air conditioning system including not only the necessary ventilating equipment, but air cooling equipment, refrigeration equipment, and cooling tower equipment associated with the refrigeration equipment. In order that the invention may be more easily understood, the operation of the system as a whole will be explained in reference with Figs. 13 and 16 of the drawings. Referring first to Fig. 13, the refrigerant compressor 20 operates in the well known fashion to compress methyl chloride or other suitable refrigerant, the compressed refrigerant being delivered to the condenser tank 21, beneath the car floor. The hot refrigerant is cooled by passing over water coils in the condenser tank 21. The refrigerant is then passed through the cooler tank 22 into expansion tubes where it expands. The expansion tubes are surrounded by water and during the expansion of the refrigerant, heat is extracted from the water, thus chilling the Water in the cooler tank 22 to a low temperature. After expansion,

the refrigerant passes back to the low pressure side of the compressor.

The water contained within the tubes of the condenser 21 becomes heated, due to cooling the compressed refrigerant, and is circulated by means of the condenser pump 23 to the cooling tower 24 where the heated water is sprayed into a spray chamber. Air from within or from outside of the car is passed through this cooling tower spray chamber 24, the heated water becoming cooled by evaporation to approximately the Wet bulb temperature of the air passing through the cooling tower. This cooled water is collected at the bottom of the cooling tower and is circulated again by the condenser pump 23 through the cooling coils in the condenser where it again acts in the next cycle to cool again the hot refrigerant.

The chilled water, which has been cooled by the expansion of the refrigerant in the cooler tank 22, is circulated by the cooler-pump 25 to the cooling chamber 26. This cooling chamber 26 may comprise a spray chamber or may be a surface cooler containing cooling piping. This is fully brought out in the following discussion of Figs. 2 and 3 of the drawings. The air to be conditioned passes into the cooling chamber 26, is there cooled, and is then passed into the car. The chilled water, after acting upon the air passing through the cooling chamber 26, is recirculated by the pump 25 again through the cooler 22 where the heat absorbed in cooling the air is withdrawn in the next cycle.

The embodiment of the invention illustrated diagrammatically by Fig. 16 utilizes the same layout as that shown by Fig. 13, except that it is much simpler. The refrigerant is compressed by the compressor 20, driven in this embodiment by an electric motor 60. This motor may be supplied with electrical current by a generator connected to an axle of the railway car, or from any other suitablesource. The compressed refrigerant is piped directly to .the condenser coils 61. The refrigerant then passes to the cooling chamber 26 and is expanded through expansion pipes in the cooling chamber to extract directly the heat from the air passing through the cooling chamber. The refrigerant before expansion is cooled by being passed through coils 61 of piping which are placed in the cooling tower spray chamber 24. The spray in this spray chamber is projected directly upon the coils 61 and thus acts to cool the refrigerant. The spray water is circulated by the condenser pump 23 through the spray chamber and the spray produced, as explained above, is cooled by evaporation to approximately the wet bulb temperature of the air passing through the spray chamber and the cooled spray, in turn, cools the hot refrigerant, this resulting in a saving in refrigeration cost. It is seen that in this embodiment of *the invention, the cooler tank 22, the condenser tank 21, and the cooled water pump 25, shown by Fig. 13, are done away with, this resulting in simpler and less expensive apparatus, and since chilled water is not circulated through the cooling chamber 26, the weight of water required to be carried is greatly reduced.

The system is arg a nged to take in 100 cubic feet of air per minute-and to discharge 100 cubic feet of air per minute. A total of 1800 cubic feet per minute is circulated through the cooling chamber and the car, this quantity being made up of 100 cubic feet per minute of new air and 1700 cubic feet per minute of recirculated air. A large amount of recirculated air is used since it should be realized that the air within the car which is recirculated is nearer the desired I temperature and humidity than the outside air so that economy is gained by treating a minimum of outside air to maintain the desired condition within the car.

Referring now to Fig. 1 of the drawings, the mechanical layout of one embodiment of the ap paratus will be explained. In the upper deck of the car, the fan unit 2'7 for circulating air through thecar, and the cooling chamber unit 26 are mounted. As will be explained in more detail later, these units are designed to be assembled together and to supporting structure of the car in order that they maybe airtight and at the same time occupy a minimum of space. All of the refrigeration equipment, including the cooling tower, condenser, compressor, motive equipment, and storage tanks, are mounted under neath the car, as indicated generally by the numeral 28.

Referring now to Figs. 1 to 7 inclusive, the arrangement of the cooling chamber unit and the ventilating fan unit will be explained in more detail. Fig. 2 is an enlarged view of the equipment shown in the upper portion of the car by Fig. 1, Fig. 2 being a side view, Fig. 5 being an upper view, and Figs. 6 and '7 being end views of this equipment. The units 26 and 27 are airtight in themselves and are arranged to be connected together and to one of the air ducts of the car so that no air leaks can take place. The brackets 28 are provided for mounting the units to the supporting structure of the car. The air from the outside enters the car through the screen 79 and the direction of the air is shown by Fig. 5. Recirculated air from the car enters the cooling chamber through the grille 29. The air passes through the cooling chamber 26 where it is cooled, passes from the cooling chamber 26, as indicated by the arrows of Fig. 5, then passes into the fan unit 2'7, then into the fan 30, into the duct 31, and then into the air duct 32 which is a part of the car extending longitudinally thereof and is provided with a plurality of spaced grids from which the air is discharged into the car from a plurality of points. The fan 30 is driven by the motor 33. The upper portion of the car is provided with a movable hatch 34, shown by Fig. 7, to permit access to the motor 33 and the cooling chamber 26.

The cooling chamber 26 may be either a spray chamber type, as indicated by Figs. 3 and 3a, or a surface cooler type, as shown by Fig. 4. The chilled water from the cooler tank 22 enters the cooling chamber through the pipe 35, then passes back to the cooler tank through the pipe 36. The cooling chamber 26, as shown by Figs. 3 and 3a, comprises a plurality of spray-heads 3'7 which project the chilled water in a direction opposing the flow of air through the cooling chamber. On the entering and leaving air end of the chamber 26 is the fine wire mesh screen 38 which filters the incoming air and also separates entrained moisture from the air leaving the cooling chamber. The elements 90 are further provided to separate any entrained moisture from the air. The cooling chamber 26, shown by Fig. 4, is of the surface type and comprises the plurality of closely spaced pipes 39 which in turn are provided with the fins 46 to give additional surface, the air passing through the chamber 26 being cooled by contact with the pipes 39 and the fins 40. It should be understood that either form of cooling chamber may be utilized with the conditioning system of this invention.

Referring nowto Figs. 8 and 9 inclusive, one embodiment of the refrigeration equipment and its accessory equipment will be explained. On the under side of the car and to one side is mounted the Water storage tank 41, the condenser 42, the cooler tank 43, and the fuel tank 44.

On the other side of the car is mounted the cooling tower 24, the air inlet 45, the refrigerant compressor 46, the fan 47, the motive power unit 48, the air exit 50, the condenser pump 23, and the cooler pump 25. All of this equipment is mounted as a unit to the under side of the car. The air enters the inlet 45 in the direction indicated by the arrows in Figs. 8 and 9, and then passes into the cooling tower 24. This cooling tower is exactly similar to the cooling chamber 26 shown by Figs. 3 and 3a, and contains a plurality of spray-heads from which the heated .Water is sprayed to be cooled by the air passing through the cooling tower. The air is drawn through the air inlet 45 by the action of the fan 47 which is driven by the engine 48 through shafting extending through the refrigerant compressor 46. The air, after leaving the cooling tower 24, passes over the compressor 46 and the motor 48 and is then discharged through the air exit 50.

A feature of the invention resides in the fact that not only is the apparatus mounted as a com pact unit, but the air from the cooling tower 24 passes over the heated compressor 46 and motor 48, and cools these heated units. Not only are the compressor 46 and the motor 48 cooled, thus enabling smaller units to be used and operated at higher capacities so that better performance is obtained by this additional cooling, but the air supplied to the carburetor of the engine 48 is clean and contains considerable moisture, both of the factors resulting in, as is well known, increased performance of internal combustion engines.

The condenser pump 23 and the cooler pump 25 are driven by the internal combustion engine by means of a belt (not shown) which passes over the pulley 51 on the engine shaft and the ply 52 on a shaft common to the two pumps.

In the embodiment of the refrigerating equipment shown by Figs. 14 and 15, an electric motor 60 is used to drive the refrigerant compressor 20, and the condenser cooler tank and cooled water pump are eliminated. These two figures of the drawings illustrate the refrigerant apparatus shown diagrammatically by Fig. 16. The refrigerant, after being compressed in the refrigerant compressor 20, is passed through the coils of pipe 61 where the spray from the nozzles 3'7 is projected upon them to cool them and the contained heated refrigerant. As explained in connection with Figs. 8 and 9, air is drawn into the air inlet 45 of the cooling tower, cools the spray water from the nozzles 3'7 by evaporation, the air being drawn by the action of the fan 47,

which is driven by the motor 60, through the to form a compact, airtight unit conveniently v mounted on the lower side of the car. By having the compressor 20 and the motor 60 cooled by the action of the cooled air passing from the cooling tower, it is possible to use a considerably smaller compressor and a considerably smaller motor, and to operate them at high capacities, this permitting the use of more compact and lighter equipment. Obviously, by reducing the size and weight of this equipment, the conditioning of railway cars and other vehicles is greatly facilitated, since one of the great disadvantages heretofore has been the great size and mass of equipment which has had to be used on vehicles which were not designed to accommodate them.

Fig. 11 is an aerograph illustrating diagrammatically the fiow of air through the cooling chamber of a railway car, conditioned according to this invention, and the temperatures at each stage of the progress of the air. The outside air, for example, in a typical situation, enters the system at the upper portion of the car at 95 dry bulb temperature and 76 wet bulb temperature. It is mixed with recirculated air from the car which, for example, has a dry bulb temperature of 77 and a wet bulb temperature of 64. 109 cubic feet per minute of outside air is taken in and 1700 cubic feet per minute of recirculated air is mixed with the outside air. The mixture of the cooled recirculated air with the outside air changes the temperature of the air to 78 dry bulb temperature and 65 wet bulb temperature.

Chilled water at 44 is supplied to the cooling chamber with the result that the air leaving the cooling chamber has wet bulb and dry bulb temperatures of 54. The cooled air passes into the railway car and cools the car and at the same time is itself heated with a result that the air passes from the car at a dry bulb temperature of 77 and a wet bulb temperature of 64. These figures are approximate and are based on actual tests and, further, on assumptions as to operating conditions which have to be met, and the figures are set up on the basis that 150 to 300 cubic feet per minute of additional outside air enters the car through leakage, and that moisture is given oil by the people in the car, and, in the case of dining cars, by the food and kitchen equipment.

Fig. 12 is an aerograph illustrating the flow of air from the cooling tower over the refrigeration system shown by Figs. 8, 9, and 13. The air for this part of the system is taken from the under side of the car and near the heated tracks with the result that the indrawn air has a higher temperature than that taken in at the top of the car. For example, the indrawn air has a dry bulb temperature of 110 and a wet bulb temperature of 78. After passing through the cool ing tower, its dry bulb and wet bulb temperatures are 85. The cooled air passing over the compressor is heated to approximately 87 dry bulb temperature and 85.5 wet bulb temperature, and next passes over the engine and is heated to 90 dry bulb temperature and wet bulb temperature. It then passes over the r'ad'ator of the engine and passes back to the tracks at a dry bulb temperature of 110 and a wet bulb temperature of 89. A similar aerograph would, of course, be applicable to the system shown by Figs. l4, l5 and 16.

Whereas one or more embodiments of the invention have been described for the purpose of illustration, it should be understood that the invention is not limited to the exact details described,

as many departures may be made by those sk lled in the art Without departing from the spirit of the invention.

What is claimed is:

1. A refrigeration system for a railway car comprising an enclosure mounted on the under side of the car and having an air inlet and an air outlet, being otherwise substantially airtight, means for projecting a spray of water into the enclosure adjacent said inlet, a sump for collecting the Water returned from said spray, means for recirculating the water from said sump to said spray, a refrigerant compressor mounted in said enclosure, a motor for driving said compressor mounted in said enclosure, and means for drawing air adjacent the railway tracks into said enclosure through said spray, over said compressor and motor, and discharging same through said outlet.

2. A refrigeration system for a ra'lway car comprising an enclosure mounted on the under side of the car and having an air inlet and an air outlet, being otherwise substantially airtight, means for projecting a spray of water into the enclosure adjacent said inlet, a sump for collecting the water returned from sa'd spray, a condenser coil for cooling the refrigerant compressed by said compressor mounted in said sump so as to be contacted with by the water collected therein, means for recirculating the water from said sump to said spray, a refrigerant compressor mounted in said enclosure, a motor for driving sad compressor mounted in said enclosure, and means for drawing air adjacent the railway tracks ,into said enclosure through said spray, over said compressor and motor, and discharging same through said outlet.

3. A refrigeration system for a railway car comprising an enclosure mounted on the under side of the car and having an air inlet and an air outlet, being otherwise substantially airtight, means for projecting a spray of water into the enclosure adjacent said inlet, a sump for collecting the water returned from said spray, means for recirculating the water from said sump to sa"d spray, a refrigerant compressor mounted in said enclosure, a motor for driving said compressor mounted in said enclosure, a filter between said spray and said compressor and motor, and means for drawing air adjacent the railway tracks into said enclosure through sa'd spray, over said compressor and motor, and discharging same through said outlet.

4. A refrigeration system for a railway car comprising an enclosure mounted on the under side of the car and having an air inlet and an air outlet, being otherwise substantially airtight, means for projecting aspray of water into the enclosure adjacent said inlet, a sump for collecting the water returned from said spray, a condenser coil for cooling the refrigerant compressed by said compressor mounted in said sump so as to be contacted with by the water collected there "n, means for recirculating the water from said sump to said spray, a-rcfrigerant compressor mounted in said enclosure, a motor for driving said compressor mounted in said enclosure, a filter between said spray and said compressor and motor, and means for drawing air adjacent the railway tracks into said enclosure through said spray, over said compressor and motor, and d'scharging same through said outlet.

SAMUEL M. ANDERSON. 

